1. Field of the Invention
The present invention relates to a transfer module and a cluster system and, more particularly, to a transfer module which can be used in a cluster system provided with a plurality of process apparatuses.
Typically, the cluster system refers to a multi-chamber manufacturing apparatus which comprises a transfer module and a plurality of process modules arranged around the transfer module.
2. Description of the Related Art
In recent years, demand for the cluster system has been increased, which cluster system can consecutively perform a plurality of processes for manufacturing a liquid crystal display (LCD), a plasma display or a semiconductor device. For example, Japanese Laid-Open Patent Application No. 10-275848 discloses a transfer module comprising an octagonal housing defining a transfer chamber and a transfer apparatus rotatably provided in the octagonal housing. A process module can be mounted to each side of the octagonal housing. The transfer apparatus takes an object to be processed such as a wafer out of a load lock cassette or a load lock chamber, and transfers the object to the process chamber of the process module. The object processed in the process chamber is taken out of the process chamber by the transfer apparatus, and transferred to another process module, the load lock module, or other modules. Generally, the transfer apparatus comprises a robot fixed in the housing in a rotatable state and a transfer arm for holding and transferring the object to be processed.
The above-mentioned conventional cluster system has some problems in relation to the transfer module. That is, the maximum number of process module that can be connected to the transfer module is limited by the shape of the housing of the transfer module. A polygonal shape such as an octagon has been adopted for the housing of the transfer module, which provides less freedom of selection and makes the housing difficult to be produced.
Accordingly, in the conventional cluster system, it is difficult to increase the number of process modules to be connected to the transfer module after the cluster system is initially established since the number of process modules that can be connected to the transfer module is limited by the shape of the housing of the transfer module. Thus, the conventional cluster system is not suitable for stepwise investment to the manufacturing facility. Additionally, the shape of the housing of the transfer module having a polygonal shape is less economic due to the difficulty in producing the housing.
Additionally, the configuration of the conventional cluster system is less efficient with respect to an area occupied by the cluster system since the process modules are arranged in the periphery of the transfer module. It should be noted that the area needed for installing the cluster system is referred to as xe2x80x9cfoot printxe2x80x9d or xe2x80x9cface printxe2x80x9d.
Further, the number of process modules to which a single transfer module can transfer the object to be processed is limited by the shape of the transfer module. That is, since the transfer apparatus, such as a robot, is fixed within the transfer module, the number of process modules to which the transfer module can access is limited to the number of sides of the transfer module housing having a polygonal shape. Accordingly, if a new cluster system is installed near an existing cluster system, the transfer apparatus or either the existing cluster system or the added cluster system cannot transfer an object to be processed between the new cluster system and the existing cluster system.
It is a general object of the present invention to provide an improved and useful transfer module and cluster system in which the above-mentioned problems are eliminated.
A more specific object of the present invention is to provide a transfer module to which an arbitrary number of process chambers can be connected so that the number of process chambers which can be connected to the transfer module can be increased after the cluster system provided with the transfer module is initially established.
Another object of the present invention is to provide a cluster system in which the number of process chambers provided therein can be increased without limitation due to the shape of the transfer module housing.
In order to achieve the above-mentioned objects, there is provided according to one aspect of the present invention a transfer module for transferring an object to be processed between a transfer chamber and at least one process chamber connected to the transfer chamber, the transfer module comprising:
a housing defining the transfer chamber, the housing having a substantially rectangular cross section so that a plurality of the housings are connectable to each other;
a movable part provided in the transfer chamber, the movable part being movable along a base surface provided in the housing;
a transfer part provided on the movable part, the transfer part holding the object to be processed and being movable between the transfer chamber and the process chamber;
a drive mechanism driving the movable part; and
a control unit controlling motion of the movable part.
According to the above-mentioned invention, the housing of the transfer module has a substantially rectangular parallelepiped shape which facilitates the production thereof. The rectangular parallelepiped shape of the housing also facilitates, combination of a plurality of the housings. That is, the transfer module can be constituted by a plurality of the housings, and the movable part can move over the plurality of the housing. Thus, the transfer part can easily access each of the process chambers connected to the transfer chamber defined by the plurality of housings.
Additionally, there is provided according to another aspect of the present invention a cluster system comprising:
at least one process module defining a process chamber, the process module applying a predetermined process to an object to be processed in the process chamber;
at least one load lock module defining a load lock chamber, the load lock module having a substantially rectangular cross section; and
a transfer module defining a transfer chamber, the transfer module transferring the object between the transfer chamber and each of the process chamber and the load lock chamber,
wherein the transfer module comprises:
a housing defining the transfer chamber, the housing having a substantially rectangular cross section so that a plurality of the housings are connectable to each other;
a movable part provided in the transfer chamber, the movable part being movable along a base surface provided in the housing;
a transfer part provided on the movable part, the transfer part holding the object to be processed and being movable between the transfer chamber and the process chamber;
a drive mechanism driving the movable part; and
a control unit controlling motion of the movable part.
According to the above-mentioned invention, the transfer module can be constituted by a plurality of housings, which increases the number of process modules connectable to the transfer module. Additionally, the movable part can move over the transfer chamber constituted by the plurality of housings, thereby enabling one transfer part to access each of the process modules connected to the transfer module.
Other objects, features and advantages of the present invention will become more apparent from the following detailed description when read in conjunction with the accompanying drawings.